scholarly journals Development of an antiseizure drug screening platform for Dravet syndrome at the NINDS contract site for the Epilepsy Therapy Screening Program

Epilepsia ◽  
2021 ◽  
Author(s):  
Chelsea D. Pernici ◽  
Jeffrey A. Mensah ◽  
E. Jill Dahle ◽  
Kristina J. Johnson ◽  
Laura Handy ◽  
...  
2020 ◽  
Author(s):  
Chelsea D. Pernici ◽  
Jeffrey A. Mensah ◽  
Elizabeth J. Dahle ◽  
Kristina J. Johnson ◽  
Laura Handy ◽  
...  

SummaryObjectiveDravet syndrome (DS) is a rare, but catastrophic genetic epilepsy, with 80% of patients with carrying a mutation in the SCN1A gene. Currently, no anti-seizure drug (ASD) exists that adequately controls seizures. Patients with DS often present clinically with a febrile seizure and generalized tonic-clonic seizures that continue throughout life. To facilitate the development of ASDs for DS, the contract site of the NINDS Epilepsy Therapy Screening Program (ETSP) has evaluated a mouse model of DS using the conditional knock-in Scn1aA1783V/WT mouse.MethodsSurvival rates and temperature thresholds for Scn1aA1783V/WT were determined. Prototype ASDs were administered via intraperitoneal injections at the time-to-peak effect, which was previously determined, prior to the induction of hyperthermia-induced seizures. Protection was determined if ASDs significantly increased the temperature at which Scn1aA1783V/WT mice seized.ResultsApproximately 50% of Scn1aA1783V/WT survive to adulthood and all have hyperthermia-induce seizures. The results suggest that hyperthermia-induced seizures in this model of DS are highly refractory to a battery of ASDs. Exceptions were clobazam, tiagabine, and the combination of clobazam and valproic acid with add-on stiripentol, which elevated seizure thresholdsSignificanceOverall, the data demonstrate the proposed model for DS is suitable for screening novel compounds for the ability to block hyperthermia-induced seizures and heterozygous mice can be evaluated repeatedly over the course of several weeks, allowing for higher throughput screening.Key PointsScn1aA1783V/WT mice have a 50% survival rate and all have hyperthermia-induced seizures.Common DS treatments such as CLB and combinatorial therapy of CLB, VPA, and STP increase temperature thresholds in Scn1aA1783V/WT mice.Sodium channel blockers, such as CBZ and LTG, decrease temperature thresholds of Scn1aA1783V/WT mice as predicted.Scn1aA1783V/WT mice are highly pharmacoresitant to common ASDsThe Scn1aA1783V/WT may be a useful preclinical drug screening platform for the treatment of DS.


2020 ◽  
Author(s):  
Melissa Barker-Haliski ◽  
Kevin M Knox ◽  
Dannielle K. Zierath ◽  
Zachery Koneval ◽  
Cameron Metcalf ◽  
...  

Objective: The kainic acid (KA)-induced status epilepticus (SE) model in rats is an etiologically-relevant animal model of epileptogenesis. Just as in patients, who develop temporal lobe epilepsy (TLE) following SE, this rat model of KA-induced SE very closely recapitulates many of the clinical and pathological characteristics of human TLE that arise following SE or another neurological insult. Spontaneous recurrent seizures (SRS) in TLE can present after a latent period following a neurological insult (TBI, SE event, viral infection, etc.). Moreover, this rat model of TLE is ideally suited for preclinical studies to evaluate the long-term process of epileptogenesis and screen putative disease-modifying/antiepileptogenic agents. This report details the pharmacological characterization and methodological refinement of a moderate-throughput drug screening program using the post KA-induced SE model of epileptogenesis in male Sprague Dawley rats to identify potential agents that may prevent or modify the onset or severity of SRS. Specifically, we sought to demonstrate whether our protocol could prevent the development of SRS, or lead to a reduced frequency/severity of SRS. Methods: Rats were administered everolimus (2-3 mg/kg, P.O. commencing at 1, 2, or 24-hrs after SE onset) or phenobarbital (60 mg/kg, beginning 1 hr after SE onset). The rats in all studies (n=12/treatment dose/study) were then followed intermittently by video-EEG monitoring; i.e., 2-weeks on/2-weeks off, 2-weeks on epochs to determine latency to onset of SRS, and disease burden following SRS onset. Results: While there were no adverse side effects observed in any of our studies, no treatment conferred a significant disease modifying effect, nor did any agent prevent the presentation of SRS by 6 weeks post-SE onset. Conclusions: While neither phenobarbital nor everolimus administered at several time points post-SE onset prevented the development of SRS, we herein demonstrate a moderate-throughput screen for potential antiepileptogenic agents in an etiologically-relevant rodent model of TLE.


2020 ◽  
Author(s):  
Alexandra Lubin ◽  
Jason Otterstrom ◽  
Yvette Hoade ◽  
Ivana Bjedov ◽  
Eleanor Stead ◽  
...  

AbstractZebrafish provide a unique opportunity for drug screening in living animals, with the fast developing, transparent embryos allowing for relatively high throughput, microscopy-based screens. However, the limited availability of rapid, flexible imaging and analysis platforms has limited the use of zebrafish in drug screens. We have developed a easy-to-use, customisable automated screening procedure suitable for high-throughput phenotype-based screens of live zebrafish. We utilised the WiScan®Hermes High Content Imaging System to rapidly acquire brightfield and fluorescent images of embryos, and the WiSoft®Athena Zebrafish Application for analysis, which harnesses an Artificial Intelligence-driven algorithm to automatically detect fish in brightfield images, identify anatomical structures, partition the animal into regions, and exclusively select the desired side-oriented fish. Our initial validation combined structural analysis with fluorescence images to enumerate GFP-tagged haematopoietic stem and progenitor cells in the tails of embryos, which correlated with manual counts. We further validated this system to assess the effects of genetic mutations and x-ray irradiation in high content using a wide range of assays. Further, we performed simultaneous analysis of multiple cell types using dual fluorophores in high throughput. In summary, we demonstrate a broadly applicable and rapidly customisable platform for high content screening in zebrafish.


2014 ◽  
Vol 59 (2) ◽  
pp. 753-762 ◽  
Author(s):  
Anita Ordas ◽  
Robert-Jan Raterink ◽  
Fraser Cunningham ◽  
Hans J. Jansen ◽  
Malgorzata I. Wiweger ◽  
...  

ABSTRACTThe translational value of zebrafish high-throughput screens can be improved when more knowledge is available on uptake characteristics of potential drugs. We investigated reference antibiotics and 15 preclinical compounds in a translational zebrafish-rodent screening system for tuberculosis. As a major advance, we have developed a new tool for testing drug uptake in the zebrafish model. This is important, because despite the many applications of assessing drug efficacy in zebrafish research, the current methods for measuring uptake using mass spectrometry do not take into account the possible adherence of drugs to the larval surface. Our approach combines nanoliter sampling from the yolk using a microneedle, followed by mass spectrometric analysis. To date, no single physicochemical property has been identified to accurately predict compound uptake; our method offers a great possibility to monitor how any novel compound behaves within the system. We have correlated the uptake data with high-throughput drug-screening data fromMycobacterium marinum-infected zebrafish larvae. As a result, we present an improved zebrafish larva drug-screening platform which offers new insights into drug efficacy and identifies potential false negatives and drugs that are effective in zebrafish and rodents. We demonstrate that this improved zebrafish drug-screening platform can complement conventional models ofin vivoMycobacterium tuberculosis-infected rodent assays. The detailed comparison of two vertebrate systems, fish and rodent, may give more predictive value for efficacy of drugs in humans.


BMC Cancer ◽  
2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Andrew Riley ◽  
Victoria Green ◽  
Ramsah Cheah ◽  
Gordon McKenzie ◽  
Laszlo Karsai ◽  
...  

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